A cellular wireless network typically includes a number of base stations that provide wireless coverage areas, such as cells and cell sectors, in which user equipment devices (UEs) such as cell phones, tablet computers, tracking devices, embedded wireless modules, and other wirelessly equipped communication devices (whether or not technically operated by a human user), can operate. In turn, each base station could be coupled with network infrastructure, including one or more gateways and switches, that provides connectivity with one or more transport networks, such as the public switched telephone network (PSTN) and/or a packet-switched network such as the Internet for instance. With this arrangement, a UE within coverage of the network could engage in air interface communication with a base station and could thereby communicate via the base station with various remote network entities or with other served UEs.
When a cellular wireless network serves UEs, the network could allocate various resources to facilitate communication to and from the UEs. In an example arrangement, for instance, the network could establish “bearers,” which could define physical or logical communication channels for carrying UE communication, such as virtual tunnels extending between the UEs a transport network gateway. Each such bearer could include a radio-bearer component that extends between a UE and a serving base station and an access-bearer component that extends between the serving base station and the transport network gateway. Further, each such bearer could have an associated service level defined by various service-level attributes, to support a particular quality of service or type of service. In practice, the network could allocate a number of such bearers for a UE, to support various different types of communication services.
By way of example, when the UE first enters into coverage of a base station, the UE could engage in a registration or “attachment” process that causes the network to establish for the UE certain default bearers for particular types of service, in accordance with the UE's service profile. For instance, if the UE's service profile indicates that the UE supports general packet-data communication (such as web browsing, file transfer, and the like), the network may establish for the UE a default bearer for carrying such communications with a best-effort service level. Further, if the UE's service profile indicates that the UE supports voice over Internet Protocol (VoIP) communications or other such real-time packet-based communication service, the network may establish for the UE a default bearer with a medium service level to support Session Initiation Protocol (SIP) signaling or the like to facilitate setup of such communications.
In turn, as a UE is being served by a base station, if the UE is going to engage in another type of communication service, the network may establish for the UE still other bearers, possibly with other service levels. For instance, if the UE supports VoIP service and seeks to engage in a VoIP call, or a VoIP call server seeks to connect a call to the UE, the network may establish for the UE a bearer with a high service level to carry the VoIP bearer traffic (e.g., packets representing voice), and the UE may then engage in the VoIP call via that bearer. Further, if the UE supports online gaming service and seeks to engage in gaming communication, the network may establish for the UE a bearer with a relatively high service level for that gaming communication, and the UE may then engage in the gaming via that bearer.
Each bearer that the network allocates to a UE could have an associated quality of service class indicator (QCI) that indicates service-level attributes of the bearer, such as whether the bearer is a “guaranteed bit rate” (GBR) bearer (having a guaranteed minimum bit rate suitable for an associated application) and if so what the GBR of the bearer is, as well as other attributes such as maximum bit rate (MBR), priority level, packet-delay budget, and packet error loss rate, for instance.
In a representative implementation, for instance, QCIs could range from 1 to 9, with QCIs 1-4 designating GBR bearers and QCIs 5-9 designating non-GBR bearers (i.e., bearers that do not have a guaranteed minimum bit rate). More specifically, in this implementation, a QCI 1 bearer is a GBR bearer for carrying conversational voice (e.g., VoIP) traffic, a QCI 3 bearer is a GBR bearer for carrying real-time gaming traffic, a QCI 5 bearer is a non-GBR bearer for carrying SIP signaling or the like, and a QCI 8 or QCI 9 bearer is a non-GBR bearer for carrying general packet-data communication.
When a base station serves a UE, the base station could maintain a context record for the UE, identifying each bearer established for the UE, and specifying the QCI level and/or other attributes of the bearer, for reference by the base station to help ensure appropriate service for the UE. To the extent the base station coordinates air interface communication with the UE on a particular bearer, the base station could work to do so in accordance with the QCI level of the bearer. For instance, when the base station coordinates transmission to the UE on a GBR bearer, the base station could work to ensure that sufficient air interface resources are allocated for that communication, to support communication at the GBR of the bearer.